DE102022116690A1 - Control device, system and control method - Google Patents

Abstract

A positional relationship between devices that have transmitted and received signals is estimated with higher accuracy. A control device includes a control unit that compares reliability parameters, which are indexes indicating a degree of whether or not a signal is appropriate as a processing target for estimating a positional relationship between each communication device of a plurality of communication devices and another communication device, based on of the signals received by the communication device from the other communication device, and performs control to estimate the positional relationship based on a signal transmitted between one communication device of the plurality of communication devices that has received a signal designated as a processing target for estimation of the positional relationship is more appropriate, and the other communication device is transmitted and received.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application is based on and claims priority from the Japanese patent application filed on Sep. 2, 2021 JP 2021-143138 , the entire contents of which are incorporated herein by reference.

BACKGROUND

The present invention relates to a control device, a system and a control method.

In recent years, a method of estimating a positional relationship between devices according to results of transmission and reception of a wireless signal between devices has been disclosed. The WO 2015-176776 A for example, discloses a method in which an ultra-wideband (UWB) receiver estimates an angle of arrival of a signal from a UWB transmitter using a UWB signal.

SHORT SUMMARY

That in the WO 2015-176776 A However, the disclosed method has a problem that although the accuracy of estimating an angle of arrival of a signal may decrease in an environment such as an environment where there is shielding between transmission and reception, no countermeasures are taken.

The present invention has therefore been made in view of the above problem, and an object of the present invention is to provide a new and improved control device, a new and improved system and a new and improved control method which establish a positional relationship between devices which transmit a signal and received, can estimate with greater accuracy.

According to an aspect of the present invention, to solve the above problem, there is provided a control device including a control unit that performs a controller for estimating a positional relationship between a plurality of communication devices each having three or more antennas and another communication device based on signals which are transmitted and received between the plurality of communication devices and the other communication device, wherein the control unit compares reliability parameters representing indices indicating a degree of whether a signal as a processing target for estimating a positional relationship between each communication device of the plurality of communication devices and the other communication device is appropriate or not, and based on the communication history provided by the respective communication device from the other direction are calculated, and performs control for estimating the positional relationship based on a signal sent and received between the communication device that has received a signal more suitable as a processing target for estimating the positional relationship and the other communication device.

According to another aspect of the present invention, to solve the above problem, there is provided a system including a plurality of communication devices each having three or more antennas, another communication device having one or more antennas, and a control device having a controller for estimating a positional relationship between the plurality of communication devices and the other communication device based on signals transmitted and received between the plurality of communication devices and the other communication device, wherein the control device compares reliability parameters representing indices indicating a degree of whether a signal as a processing target for estimating a positional relationship between each communication device of the plurality of communication devices and the other communication device g is appropriate or not, and which are calculated based on the signals received by the respective communication device from the other communication device, and performs control for estimating the positional relationship based on a signal transmitted between the communicator tion device that has received a signal more suitable as a processing target for estimating the positional relationship and the other communication device is transmitted and received.

According to another aspect of the present invention, to solve the above problem, there is provided a computer-executed control method of transmitting and receiving signals between a plurality of communication devices each having three or more antennas and another communication device, and performing control for estimating a positional relationship between the plurality of communication devices and the other communication device based on the transmitted and received signals, wherein performing the control for estimating a positional relationship between the plurality of communication devices and the other communication device includes comparing reliability parameters representing indices that indicate a degree of whether a signal as a processing target for estimating a positional relationship between each communication device of the plurality of K communication devices and the other communication device is appropriate or not, and which are calculated based on the signals received by the respective communication device from the other communication device, and performing a control for estimating the positional relationship based on a signal between the communication device that has received a signal more suitable as a processing target for estimating the positional relationship and the other communication device is transmitted and received.

As described above, according to the present invention, it is possible to estimate a positional relationship between devices that transmit and receive a signal with high accuracy.

character list

• 1 12 is a block diagram showing an example of a configuration of a system 1 according to an embodiment of the present invention.
• 2 12 is an explanatory view for describing an outline example of the system 1 according to the present embodiment.
• 3 12 is a diagram showing an example of a communication processing block of a communication unit 220 according to the present embodiment.
• 4 12 is a graph showing an example of a CIR output from an integrator 229 according to the present embodiment.
• 5 12 is a diagram showing an example of a communication processing block of the communication unit 220 according to the present embodiment.
• 6A FIG. 12 is an explanatory view for describing an example of a weight parameter calculation method according to a first determined value.
• 6B FIG. 12 is an explanatory view for describing an example of a weight parameter calculation method using a linear function as a specific function.
• 6C Fig. 12 is an explanatory view for describing an example of a weight parameter calculation method using a trigonometric function as a specific function.
• 6D Fig. 12 is an explanatory view for describing an example of a weight parameter calculation method using an exponential function as a specific function.
• 7A FIG. 12 is an explanatory view for describing an example of a weight parameter calculation method according to the first determined value.
• 7B FIG. 12 is an explanatory view for describing an example of a weight parameter calculation method using a linear function as a specific function.
• 7C Fig. 12 is an explanatory view for describing an example of a weight parameter calculation method using a trigonometric function as a specific function.
• 7D Fig. 12 is an explanatory view for describing an example of a weight parameter calculation method using an exponential function as a specific function.
• 8th Fig. 12 is an explanatory view for describing an example of a working process of the system 1 related to Example 1.
• 9 12 is a block diagram showing a configuration example of a vehicle 20 related to Example 2 and Example 3.
• 10 Fig. 14 is an explanatory view for describing a control example of the system 1 related to example 2.
• 11 Fig. 12 is an explanatory view for describing an example of a working process of the system 1 related to example 2.
• 12 Fig. 14 is an explanatory view for describing a control example of the system 1 related to example 3.
• 13 Fig. 14 is an explanatory view for describing another control example of the system 1 related to example 3.
• 14 Fig. 12 is an explanatory view for describing an example of a working process of the system 1 related to Example 3.

DETAILED DESCRIPTION OF EMBODIMENTS

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional structure are given the same reference numerals, and thus redundant description is omitted.

In the present description and drawings, components having essentially the same functional structure can be distinguished by adding different letters or numbers after the same reference number. For example, a plurality of components having substantially the same functional structure are differentiated as needed as in-vehicle devices 200-1 and 200-2. If it is not necessary to distinguish a large number of components with essentially the same functional structure from one another, the same reference number is simply used. For example, in a case where distinction between the in-vehicle devices 200 - 1 and 200 - 2 is not required, they are simply referred to as the in-vehicle device 200 .

1. Configuration example

1 12 is a block diagram showing an example of a configuration of a system 1 according to an embodiment of the present invention. like it in 1 1, the system 1 according to the present embodiment includes a portable device 100, an in-vehicle device 200, a control device 300, and a working device 400.

The in-vehicle device 200 , the control device 300 , and the working device 400 according to the present embodiment are mounted on the vehicle 20 . The vehicle 20 is an example of a moving object, and is, for example, a vehicle registered to a user (e.g., a vehicle that the user owns or a vehicle that the user temporarily rents). A moving object according to the present embodiment includes not only the vehicle 20 but also an airplane, a ship, and the like.

Portable device 100

The portable device 100 is an example of another communication device, and is a device carried by a user who is currently using the vehicle 20 . The portable device 100 may be an electronic key, a smartphone, a tablet device, a wearable device, or the like. like it in 1 As shown, the portable device 100 includes a control unit 110 and a communication unit 120.

The control unit 110 controls the overall operation of the portable device 100. The control unit 110 causes the communication unit 120 to transmit, for example, a poll (polling) signal, which will be described later. The control unit 110 causes the communication unit 120 to send a final signal, which will be described later. The control unit 110 is configured with, for example, electronic circuits such as a central processing unit (CPU) and a microprocessor.

The communication unit 120 performs wireless communication with a communication unit 220 included in the in-vehicle device 200 . The communication unit 120 transmits, for example, a Poll signal under the control of the control unit 110. The communication unit 120 receives a Resp (Response) signal transmitted from the communication unit 220 included in the in-vehicle device 200 in response to the transmitted Poll- Signal. The communication unit 120 transmits a Final signal in response to the received Resp signal under the control of the control unit 110.

The wireless communication between the communication unit 120 and the communication unit 220 included in the in-vehicle device 200 is realized by, for example, a signal compliant with ultra-wideband wireless communication (hereinafter referred to as a UWB signal).

In a case where a pulse method is used in wireless communication using a UWB signal, it is possible to measure an air propagation time of radio waves with high accuracy using radio waves with a very short pulse width of nanoseconds or less, and therefore a To perform position and distance measurement based on propagation time with great accuracy. The communication unit 120 is configured, for example, as a communication interface that can perform communication using a UWB signal.

The UWB signal can be sent and received as a distance measurement signal and as a data signal. The ranging signal is any one of a poll signal, a resp signal, and a final signal that is transmitted and received in a ranging process that will be described later. The ranging signal may be configured in a frame format with no payload section for storing data, or may be configured in a frame format with a payload section. On the other hand, the data signal is preferably configured in a frame format with a payload portion for storing data.

The communication unit 120 has at least one antenna 121 . The communication unit 120 transmits and receives a wireless signal via at least one antenna 121.

Device in vehicle 200

The in-vehicle device 200 is an example of a communication device and is a device mounted on the vehicle 20 . like it in 1 As shown, the in-vehicle device 200 includes a control unit 210 and a communication unit 220.

The control unit 210 controls the overall operation of the in-vehicle device 200. The control unit 210 causes the communication unit 220 to transmit, for example, a Resp signal, which will be described later. The control unit 210 is configured with, for example, electronic circuits such as a CPU and a microprocessor.

The communication unit 220 performs wireless communication with the communication unit 120 included in the portable device 100 . The communication unit 220 receives a poll signal sent from the communication unit 120 included in the portable device 100 . The communication unit 220 transmits a Resp signal under the control of the control unit 210 in response to the received Poll signal. The communication unit 220 receives the final signal transmitted from the communication unit 120 included in the portable device 100 in response to the transmitted Resp signal.

The communication unit 220 has at least three or more antennas 221 . The communication unit 220 transmits and receives wireless signals via three or more antennas 221. However, in a case where the control device 30 according to the present invention is applied to Example 1 described later, the communication unit 220 needs at least four or more antennas 221.

Controller 300

The control device 300 performs control to calculate a positional relationship between the portable device 100 and the in-vehicle device 200 . As in 1 shown contains the Control device 300 includes a communication unit 310 and a control unit 320. Here, an example will be described in which the vehicle 20 according to the present embodiment is configured such that the in-vehicle device 200 and the control device 300 are provided separately; however, a function of the control device 300 may be realized by the portable device 100 or the in-vehicle device 200 .

The communication unit 310 uses any communication method to perform various communications with the in-vehicle device 200. The communication unit 310 receives, for example, information regarding a signal transmitted and received between the portable device 100 and the in-vehicle device 200 from the signal contained in the in-vehicle device 200 Communication unit 220. Any communication method may include wired communication or wireless communication. The communication unit 310 can perform various communications with the communication unit included in the portable device 100 using a wireless communication method.

The control unit 320 controls the overall operation of the control device 300. The control unit 320 performs control to estimate a positional relationship between the portable device 100 and the in-vehicle device 200 based on, for example, one transmitted and received between the portable device 100 and the in-vehicle device 200 signal through. like it in 1 As shown, the control unit 320 includes a parameter calculation unit 321 and a position estimation unit 325.

The control unit 320 is configured by electronic circuits such as a CPU and a microprocessor, for example.

The parameter calculation unit 321 calculates a reliability parameter based on a signal transmitted and received between the in-vehicle device 200 and the portable device 100, which is an index indicating the degree of whether the signal is used as a processing target for estimating a positional relationship between the portable device 100 and the in-vehicle device 200 is suitable or not. Details of the reliability parameter will be described later.

The position estimating unit 325 estimates a positional relationship between the portable device 100 and the in-vehicle device 200 based on the transmitted and received signal between the portable device 100 and the in-vehicle device 200 . For example, the position estimating unit 325 calculates a distance measurement value between the portable device 100 and the in-vehicle device 200 based on the transmitted and received signal between the portable device 100 and the in-vehicle device 200 . The position estimating unit 325 estimates an angle of arrival of a signal based on the signal received by the in-vehicle device 200 from the portable device 100 . The position estimating unit 325 calculates a two-dimensional position or a three-dimensional position of the portable device 100 based on the calculated distance measurement value and the angle of arrival of the signal. Various processes related to estimating a positional relationship are performed using the reliability parameter calculated by the parameter calculation unit 321, and the details thereof will be described later.

Working device 400

The working device 400 is a device operated under the control of the control device 300 . The working device 400 may be a door key of the vehicle 20 or an engine of the vehicle 20 .

The configuration example of the system 1 according to the present embodiment has been described above. In the following, with reference to the 2 until 5 technical features of the system 1 described according to the present embodiment.

2. Technical characteristics

2.1. multipath environment

In processes based on a signal transmitted and received between the portable device 100 and the in-vehicle device 200, the estimation accuracy of a positional relationship may decrease depending on a radio wave propagation environment.

As an example of such a situation, there is a case where an object such as a pillar is present in a communication path from the antenna 121 to the antenna 221 . In this case, for example, reception power of a transmitted and received signal may decrease, and thus estimation accuracy of a positional relationship may decrease.

Another example of such a situation is a situation where multipath occurs. The multipath refers to a state where a plurality of radio waves sent from a certain transmitter (e.g., the communication unit 120) arrive at the receiver (e.g., the communication unit 220), and occurs in a case where between the transmitter and the receiver of a plurality of radio wave paths. In a situation where multipath occurs, radio waves traveling through a plurality of different paths may interfere with each other, and so the estimation accuracy of a positional relationship may be reduced.

Therefore, a positional relationship between the portable device 100 and the in-vehicle device 200 estimated by the position estimating unit 325 may include an estimation error due to the multipath environment. Therefore, the control device 300 according to the present embodiment estimates a positional relationship between the portable device 100 and the in-vehicle device 200 using a reliability parameter that is an index indicating the degree of whether a signal as a processing target for estimating the positional relationship between the portable device 100 and the in-vehicle device 200, which is calculated based on the signal received by the in-vehicle device 200 from the portable device 100, is appropriate or not. Thereby, the influence of an estimation error of a positional relationship caused by the above multipath environment can be reduced.

An outline example of the system 1 according to the present embodiment will be explained below with reference to FIG 2 described.

2 12 is an explanatory view for describing an outline example of the system 1 according to the present embodiment. As in 2 As shown, the communication unit 120 included in the portable device 100 has the antenna 121 . The communication unit 220 included in the in-vehicle device 200 includes, for example, an antenna 221A, an antenna 221B, an antenna 221C, and an antenna 221D as a four-element array antenna. However, the number of antennas included in the communication unit 120 included in the portable device 100 and the communication unit 220 included in the in-vehicle device 200 is not limited to the above example. The number of antennas of the communication unit 120 may be plural, and the number of antennas 221 of the communication unit 220 may be five or more. In the case of applying the control device 300 according to the present invention to the example 2 or to the example 3 which will be described later, the communication unit 220 may have three antennas 221 .

A scale ratio of the communication unit 220 and the plurality of antennas 221 of the communication unit 220 is not limited to a scale ratio shown in the figure. For example, the antenna 221A, the antenna 221B, the antenna 221C, and the antenna 221D may each be arranged at intervals of about half a wavelength. An arrangement shape of the four antennas may be a square shape, a parallelogram shape, a trapezoidal shape, a rectangular shape, and any other shapes. However, the plurality of antennas 221 should be arranged on a plane, not on the same straight line.

According to 2 For example, the antenna 121 of the portable machine 100 is arranged at the upper left end of the portable machine 100, however, an arrangement position of the antenna 121 of the portable machine 100 is not limited to the above example. The antenna 121 can be arranged at any position in the portable device 100, for example.

like it in 2 As shown, the antenna 121 can transmit and receive a signal S to and from at least one of the plurality of antennas 221 of the communication unit 220, for example.

The communication unit 310 included in the control device 300 receives information regarding the signal transmitted and received between the portable device 100 and the in-vehicle device 200 from either the communication unit 120 or the communication unit 220. Thereafter, the parameter calculation unit 321 can calculate a reliability parameter based on the transmitted and Calculate received signal S. The position estimating unit 325 may estimate a positional relationship between the portable device 100 and the in-vehicle device 200 based on the signal S transmitted and received.

2.2. CIR calculation process

The communication unit 120 included in the portable device 100 and the communication unit 220 included in the in-vehicle device 200 according to the present embodiment can calculate a channel impulse response (CIR), the characteristics of a wireless communication path between the communication unit 120 and the communication unit 220 indicates.

The CIR is calculated in the present application by one of the communication unit 120 and the communication unit 220 (hereinafter also referred to as the transmitting side) which transmits a wireless signal containing a pulse, and the other (hereinafter also referred to as the receiving side) that receiving wireless signal. More specifically, the CIR in this application is a correlation calculation result, which is a result showing a correlation between the wireless signal transmitted by the transmission side (hereinafter also referred to as transmitted signal) and the wireless signal received by the reception side (hereinafter also referred to as a received signal) is performed for each delay time that is an elapsed time after the transmitted signal was sent.

The receiving side calculates the CIR by performing a sliding correlation between the transmitted signal and the received signal. More specifically, the receiving side calculates a value obtained by correlating the received signal with the transmitted signal delayed by a certain delay time as a characteristic (hereinafter also referred to as a CIR value) in the delay time. The receiving side calculates the CIR by calculating a CIR value for each delay time. That is, the CIR is a time series transition of the CIR values. Here, the CIR value is a complex number with an I component and a Q component. A sum of squares of the I component and the Q component of the CIR value can also be referred to as the power value of the CIR. In a distance measurement method using UWB, the CIR value is also referred to as the delay profile. In the distance measurement method using UWB, a sum of squares of the I component and the Q component of the CIR value is also called a power delay profile.

A CIR calculation process in a case where the transmission side is the portable device 100 and the reception side is the in-vehicle device 200 will be described below with reference to FIG 3 and 4 described in more detail.

3 12 is a diagram showing an example of a communication processing block of the communication unit 220 according to the present embodiment. As in 3 As shown, the communication unit 220 includes an oscillator 222, a multiplier 223, a 90 degree phase shifter 224, a multiplier 225, a low pass filter (LPF) 226, an LPF 227, a correlator 228 and an integrator 229.

The oscillator 222 generates a signal having the same frequency as a frequency of a carrier wave carrying the transmitted signal, and outputs the generated signal to the multiplier 223 and the 90-degree phase shifter 224 .

The multiplier 223 multiplies the reception signal received by the antenna 221 by the signal output from the oscillator 222 and outputs a result of the multiplication to the LPF 226 . The LPF outputs a signal having a frequency equal to or less than the frequency of the carrier wave carrying the transmitted signal among input signals to the correlator 228 . That into the correlator 228 The inputted signal is the I component (ie, the real part) of components corresponding to an envelope of the received signal.

The 90 degree phase shifter 224 delays a phase of the input signal by 90 degrees and outputs the delayed signal to the multiplier 225 . The multiplier 225 multiplies the reception signal received by the antenna 221 and the signal output from the 90-degree phase shifter 224 and outputs a result of the multiplication to the LPF 227 . The LPF 227 outputs a signal having a frequency equal to or less than the frequency of the carrier wave carrying the transmitted signal from input signals to the correlator 228 . The signal input to the correlator 228 is the Q component (i.e., the imaginary part) of the components that correspond to the envelope of the received signal.

The correlator 228 calculates the CIR by performing a sliding correlation between the received signal configured with the I component and the Q component output from the LPF 226 and the LPF 227 and a reference signal. The reference signal here is the same signal as the transmitted signal before the carrier wave is multiplied.

The integrator 229 integrates the CIR output from the correlator 228 and outputs it.

The communication unit 220 performs the above process for each of the received signals received by the plurality of antennas 221 .

4 FIG. 12 is a graph showing an example of the CIR output from the integrator 229 according to the present embodiment. The horizontal axis of the graph is a delay time and the vertical axis is a delay profile. A piece of information constituting information that changes over time, such as a CIR value at a certain delay time in the CIR, is also referred to as a sampling point. Typically, in CIR, a set containing sample points between zero-crossing points corresponds to a single pulse. A zero crossing point is a sampling point where a value becomes zero. However, this does not apply to a noisy environment. For example, a set of sample points between crossing points of a non-zero reference level and a transition in the CIR value can be considered to correspond to an impulse. In the 4 The CIR shown contains a set 21 of sample points corresponding to a particular pulse and a set 22 of sample points corresponding to another pulse.

Set 21 corresponds, for example, to a faster path pulse. A fast path refers to the shortest path between transmission and reception and refers to a linear distance between transmission and reception in an environment where there is no shielding. A fast path pulse is a pulse that reaches a receiving side through a fast path. For example, the set 22 corresponds to a pulse arriving at a receiving side through a path other than the fast path.

A pulse that is detected as a fast-path pulse is also called the first arrival wave. The first arrival wave can be a direct wave, a delayed wave, or a composite wave. The direct wave is a signal directly received (i.e., without being reflected or the like) by a receiving side via the shortest path between transmission and reception. That is, the direct wave is a faster path pulse. The delayed wave is a signal received indirectly by the receiving side via a non-shortest path between transmission and reception, i. i.e. reflected or the like. The delayed wave is received by the receiving side with a delay compared to the direct wave. A composite wave is a signal received by the receiving side in a state where a plurality of signals having passed through a plurality of different paths are combined. In the present description, the first arrival wave is sometimes referred to simply as a signal.

An example of a flow of processing related to estimation of a positional relationship between the portable device 100 and the in-vehicle device 200 according to the present embodiment will be described below.

2.3. Estimation of a positional relationship

(1) Distance estimation

The position estimating unit 325 performs a distance measuring process. The distance measurement process is a process of estimating the distance between the portable device 100 and the in-vehicle device 200. The distance measurement process includes transmitting and receiving a distance measurement signal and estimating a distance between the portable device 100 and the in-vehicle device 200, i. i.e., a distance measurement value based on the time required to transmit and receive the distance measurement signal.

In the ranging process, a plurality of ranging signals may be transmitted and received between the portable device 100 and the in-vehicle device 200 . Among the plurality of ranging signals, a ranging signal sent from one device to the other device is referred to as a poll signal. A ranging signal sent in response to the poll signal from the device that received the poll signal to the device that sent the poll signal is referred to as a resp signal. A ranging signal sent from the device that received the Resp signal to the device that sent the Resp signal in response to the Resp signal is referred to as a final signal. Although the portable device 100 and the in-vehicle device 200 can transmit and receive each of the ranging signals, an example in which the portable device 100 transmits a poll signal is described in the present application.

(2) Angle of incidence estimation

The position estimating unit 325 estimates an angle of arrival of a signal transmitted and received between the devices. In the present application, a final signal included in the distance measurement signals is described as a signal for estimating an angle of arrival.

An example of a process related to range estimation and angle of incidence estimation is given below with reference to FIG 5 described.

5 14 is a flowchart for describing an example of a process related to positional relationship estimation between devices, which is executed in the system 1 according to the present embodiment.

First, the antenna 121 of the portable device 100 transmits a poll signal to the antenna 221A of the in-vehicle device 200 (S101).

Next, the antenna 221A of the in-vehicle device 200 transmits a Resp signal to the antenna 121 of the portable device 100 in response to the poll signal (S103).

The antenna 121 of the portable device 100 transmits a final signal to the antenna 221A, the antenna 221B, the antenna 221C, and the antenna 221D of the in-vehicle device 200 in response to the Resp signal (S105).

Here, a period of time from the transmission of the poll signal to the reception of the resp signal by the portable device 100 is set as a period T1, and a period of time from the reception of the resp signal to the transmission of the final signal is set as a period T2. A period from receiving the Poll signal to sending the Resp signal by the in-vehicle device 200 is set as a period T3, and a period from sending the Resp signal to receiving the Final signal is set as a period T4.

A distance between the portable device 100 and the in-vehicle device 200 may be calculated using any of the above time periods. For example, the in-vehicle device 200 may receive a signal containing information regarding the time period T1 and the time period T2 from the portable device 100 . The control device 300 may receive a signal including information regarding the time period T1, the time period T2, the time period T3, and the time period T4 from the in-vehicle device 200. FIG. The position estimating unit 325 calculates a signal propagation time τ using the period T1, the period T2, the period T3, and the period T4. More accurate In other words, the position estimating unit 325 can calculate the signal propagation time τ using Equation 1 below. $$\text{T}=\left(\text{<figure-callout id="1" label="T" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">T</figure-callout>}1\times \text{T}4-\text{<figure-callout id="2" label="T" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">T</figure-callout>}2\times \text{T}3\right)\text{/}\left(\text{<figure-callout id="1" label="T" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">T</figure-callout>}1+\text{<figure-callout id="2" label="T" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">T</figure-callout>}2+\text{T}3+\text{T}4\right)$$

The position estimating unit 325 may estimate a distance between the portable device 100 and the in-vehicle device 200 by multiplying the calculated signal propagation time τ by a known signal speed.

An example in which the position estimating unit 325 estimates the distance between the portable device 100 and the in-vehicle device 200 based on a signal transmitted between the antenna 121 of the portable device 100 and the antenna 221A of the in-vehicle device 200 has been described and is received, however, the in-vehicle device 200 may transmit and receive a signal using a different antenna from the antenna 221A, or may transmit and receive a signal using a plurality of antennas 221 .

The signal propagation time τ is not limited to a calculation method based on equation (1). The signal propagation time τ can also be calculated, for example, by subtracting the time duration T3 from the time duration T1 and dividing this time by 2.

Next, an angle of arrival of a signal can be calculated from a phase difference of a final signal received by an adjacent antenna among the plurality of antennas 221 of the in-vehicle device 200 . For example, a phase of the final signal received by antenna 221A is set as phase P _A , a phase of the final signal received by antenna 221B is set as phase P _B , a phase of the final signal received by antenna 221C is set as phase P _C is set and a phase of the final signal received by the antenna 221D is set as phase P _D .

For example, a coordinate system is defined in which a straight line connecting the antenna 221A and the antenna 221B represents an X-axis, a straight line connecting the antenna 221A and the antenna 221C orthogonal to the X-axis represents a represents Y-axis, and a vertical direction of antenna 221A represents Z-axis.

In the case of such a coordinate system, phase differences Pd _AB and Pd _CD between antennas adjacent to each other in the X-axis direction and phase differences PD _AC and Pd _BD between the antennas adjacent to each other in the Y-axis direction are expressed by the following Equation 2, respectively. $$\begin{array}{c}{\text{Pd}}_{\text{AWAY}}=\left({\text{P}}_{\text{B}}-{\text{P}}_{\text{A}}\right)\\ {\text{Pd}}_{\text{CD}}=\left({\text{P}}_{\text{D}}-{\text{P}}_{\text{C}}\right)\\ {\text{Pd}}_{\text{AC}}=\left({\text{P}}_{\text{C}}-{\text{P}}_{\text{A}}\right)\\ {\text{Pd}}_{\text{BD}}=\left({\text{P}}_{\text{D}}-{\text{P}}_{\text{B}}\right)\end{array}$$

Here, an angle formed between the straight line connecting the antenna 221A and the antenna 221B (or the antenna 221C and the antenna 221D) and the first arrival wave is referred to as a generated angle θ. An angle formed between the straight line connecting the antenna 221A and the antenna 221C (or the antenna 221B and the antenna 221D) and the first arrival wave is called a generated angle φ. Here, the generated angle θ and the generated angle φ are angles of incidence of a signal, respectively, and are expressed by Equation 3. Here, λ represents a wavelength of a radio wave, and d is a distance between the antennas. $$\mathrm{\theta }\text{or}\mathrm{\phi }=\text{arccos}\left(\mathrm{\lambda }\times \text{pd/}\left(2\mathrm{\pi }\text{i.e}\right)\right)$$

The position estimating unit 325 therefore calculates an angle of arrival of a signal using Equation 4 based on Equations 2 and 3. $$\begin{array}{c}{\mathrm{\theta }}_{\text{AWAY}}=\text{arccos}\left(\mathrm{\lambda }\times \left({\text{P}}_{\text{B}}-{\text{P}}_{\text{A}}\right)\text{/}\left(2\mathrm{\pi }\text{i.e}\right)\right)\\ {\mathrm{\theta }}_{\text{CD}}=\text{arccos}\left(\mathrm{\lambda }\times \left({\text{P}}_{\text{D}}-{\text{P}}_{\text{C}}\right)\text{/}\left(2\mathrm{\pi }\text{i.e}\right)\right)\\ {\mathrm{\phi }}_{\text{AWAY}}=\text{arccos}\left(\mathrm{\lambda }\times \left({\text{P}}_{\text{C}}-{\text{P}}_{\text{A}}\right)\text{/}\left(2\mathrm{\pi }\text{i.e}\right)\right)\\ {\mathrm{\phi }}_{\text{BD}}=\text{arccos}\left(\mathrm{\lambda }\times \left({\text{P}}_{\text{D}}-{\text{P}}_{\text{B}}\right)\text{/}\left(2\mathrm{\pi }\text{i.e}\right)\right)\end{array}$$

The position estimating unit 325 may calculate the angle θ that forms an average of θ _AB and θ _CD , or may estimate the angle θ that forms either θ _AB or θ _CD . Likewise, the position estimation unit 325 can calculate the angle φ that forms an average of φ _AC and φ _BD , or can estimate the angle φ that forms either φ _AC or φ _BD .

The position estimating unit 325 may estimate a two-dimensional position or a three-dimensional position of the portable device 100 using the estimated distance measurement value and the generated angle θ or the generated angle φ.

In the coordinate system described above, the position estimating unit 325 can estimate a three-dimensional position of the portable device 100 using Equation 5, for example. $$\begin{array}{c}\text{X}=\text{R}\times \text{cos}\mathrm{\theta }\\ \text{Y}=\text{R}\times \text{cos}\mathrm{\phi }\\ \text{Z}=\surd \left(\text{<figure-callout id="2" label="R" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">R</figure-callout>}2-\text{x}2-\text{y}2\right)\end{array}$$

As described above, the position estimating unit 325 may estimate a positional relationship between the portable device 100 and the in-vehicle device 200 based on the signals transmitted between the plurality of antennas 221 of the in-vehicle device 200 and the antennas 121 of the portable device 100 and be received. On the other hand, as described above, the estimation accuracy of a positional relationship may be reduced depending on the multipath environment generated between the plurality of antennas 221 of the in-vehicle device 200 and the antennas 121 of the portable device 100 .

The position estimating unit 325 therefore calculates, based on a signal received by any of the antennas of the in-vehicle device 200 or the antenna 121 of the portable device 100, a reliability parameter indicating the degree of whether signals between the plurality of antennas 221 of the in-vehicle device 200 and the antenna 121 of the portable device 100 are transmitted and received as processing targets for estimating a positional relationship or not. By using a positional relationship estimation signal for which the reliability parameter satisfies a predetermined criterion, the position estimation unit 325 can estimate a positional relationship between the portable device 100 and the in-vehicle device 200 with higher accuracy.

A specific example of the reliability parameter calculated by the parameter calculation unit 321 will be described below.

2.4. reliability parameters

The parameter calculation unit 321 according to the present embodiment calculates a reliability parameter based on a signal received by the communication unit 220 . Here, the received signal may be the above poll signal, resp signal, or final signal, or may be a signal sent from the portable device 100 separately from the ranging signal.

The reliability parameter is an index indicating the degree of whether a signal received by the antenna 121 of the communication unit 120 or any of the antennas 221 of the communication unit 220 is used as a processing target for estimating a positional relationship between the portable device 100 and the device in the vehicle 200 is suitable or not. The reliability parameter is, for example, a continuous value or a discrete value, and as its value increases, a signal transmitted and received through the antennas becomes more suitable as a processing target for estimating a positional relationship, for example, and as the value decreases, the signal becomes processing target for estimating a positional relationship, for example, unsuitable. When a value of the reliability parameter increases, a signal transmitted and received by the antennas becomes less suitable as a processing target for estimating a positional relationship, for example, and when the value decreases, the signal becomes more suitable as a processing target for estimating a positional relationship, for example. A reliability parameter based on a signal received by the communication unit 220 will be described below with reference to specific examples.

Index indicating the magnitude of noise

For example, the reliability parameter may be an index indicating a magnitude of noise. More specifically, the parameter calculation unit 321 may calculate the reliability parameter based on a power value and/or a signal-to-noise ratio (SNR) of a signal received by the communication unit 220 . Since the influence of noise is small in a case where the power value or the SNR is large, a first reliability parameter indicating that the first arrival wave is suitable as a detection target is calculated. On the other hand, since the influence of noise is large in a case where the power value or the SNR is small, a reliability parameter indicating that the first arrival wave is unsuitable as a detection target can be calculated.

Index indicating validity that first arrival wave is based on a direct wave

The reliability parameter is an index indicating the validity that the first arrival wave is due to a direct wave. The greater the validity that the first arrival wave is based on a direct wave, the greater the reliability, and the lower the validity that the first arrival wave is based on a direct wave, the lower the reliability.

The reliability parameter may be calculated based on the consistency between signals at each of the plurality of antennas 221 of the communication unit 220, for example. More specifically, the parameter calculation unit 321 may calculate a reliability parameter based on a signal reception time and/or a power value at each of the plurality of antennas 221 of the communication unit 220 . Due to the influence of the multipath, a plurality of signals arriving via different paths can be combined and received by the antennas in a state of reinforcing or canceling each other. In a case where the manner of amplifying and canceling a signal is different at each of the plurality of antennas, the receiving time and the power value of the signal may be different among the plurality of antennas. Considering that a distance between the antennas is a short distance of about half a wavelength of a signal for estimating an angle of arrival means a large difference in a signal receiving time and a power value between the antenna 221A, the antenna 221B, the antenna 221C and the antenna 221D that the validity that the signal is based on a direct wave becomes lower.

Therefore, a reliability parameter is calculated indicating that the validity that the first arrival wave is based on a direct wave becomes lower as a difference in reception time of the first arrival wave (i.e., a delay time of a certain element) between the plurality of antennas 221 becomes larger becomes. On the other hand, a reliability parameter indicating that the validity that the first arrival wave is based on a direct wave becomes larger as a difference in reception timing of the first arrival wave between the plurality of antennas 221 becomes smaller is calculated. A reliability parameter is calculated indicating that the validity that the first arrival wave is based on a direct wave becomes smaller as a difference in power of the first arrival wave between the plurality of antennas 221 becomes larger. On the other hand, a reliability parameter indicating that the validity that the first arrival wave is based on a direct wave becomes larger as a difference in power of the first arrival wave between the plurality of antennas 221 becomes smaller is calculated.

The reliability parameter can be calculated based on the consistency between position parameters indicating a position where the portable device 100 is located and estimated based on the first arrival wave received by each of a plurality of antenna pairs transmitted by two different Antennas (e.g., the antenna 221A and the antenna 221B) are formed of the plurality of antennas 221 . The position parameters here are the distance measurement, the generated angles θ and φ, and the coordinates (x,y,z).

In a case where the first arrival wave is based on a direct wave, results of the generated angles θ and φ and the coordinates (x,y,z) are the same or substantially the same even if combinations of antenna pairs of the communication unit 220 used for calculation the generated angles θ and φ and the coordinates (x,y,z) used are different. However, in a case where the first arrival wave is not based on a direct wave, there may be differences in results of the generated angles θ and φ and the coordinates (x,y,z) at different antenna pairs of the communication unit 220.

Therefore, a reliability parameter indicating that the validity that the first arrival wave is based on a direct wave becomes larger as a difference in a calculation result of a position parameter between combinations of different antenna pairs becomes smaller is calculated. For example, a reliability parameter is calculated indicating that the validity that the first arrival wave is due to a direct wave increases as an error between φ _AC and φ _BD and an error between θ _AB and θ _CD described in the angle estimation process , are reduced. On the other hand, a reliability parameter indicating that the validity that the first arrival wave is based on a direct wave becomes smaller as a difference in a calculation result of a position parameter between combinations of different antenna pairs becomes larger is calculated. For example, a reliability parameter is calculated indicating that the validity that the first arrival wave is due to a direct wave becomes smaller as an error between φ _AC and φ _BD and an error between θ _AB and θ _CD described in the angle estimation process , climb. However, a reliability parameter calculated using differences in the generated angles θ and φ and the coordinates (x,y,z) is a reliability parameter for the entire antenna, and thus is not applied to Example 1 described later becomes.

Index indicating validity that first arrival wave is not based on a composite wave

The reliability parameter may be an index indicating the validity that the first arrival wave is not due to a composite wave. The greater the validity that the first arrival wave is not due to a composite wave, the higher the reliability, and the lower the validity that the first arrival wave is not due to a composite wave, the lower the reliability. In particular, the reliability parameter may be calculated based on a width in time direction of the first arrival wave and/or a phase state at the first arrival wave.

Index indicating the validity of a situation in which a radio or wireless signal is received

The reliability parameter can be an index indicating the validity of a situation in which a wireless signal is received. The higher the validity of a situation where a wireless signal is received, the higher the reliability, and the lower the validity of the situation where the wireless signal is received, the lower the reliability.

For example, the reliability parameter may be calculated based on a variation of a plurality of first arrival waves. In this case, the reliability parameter can be calculated based on a statistic indicating a variation of a plurality of first arrival waves, such as a variance of power values of the first arrival waves and variances and amounts of change in the estimated position parameters (the distance of the generated angles θ and φ and of coordinates (x,y,z)).

Difference between delay time of a first element and delay time of a second element

The reliability parameter may be a difference between a delay time of a first item at which a CIR value peaks after a particular item in the CIR for the first time and a delay time of a second item at which the CIR value peaks after the specific item reached the top for the second time. As in 4 As shown, a CIR waveform of the first arrival wave is a peaked waveform. On the other hand, when a composite wave is detected as the first arrival wave, a CIR waveform of the first arrival wave may be a waveform having a plurality of peaks. Whether the CIR waveform of the first arrival wave is a spike or a spike has a plurality of peaks can be determined based on a difference between the delay time of the first element and the delay time of the second element.

In a case where a composite wave is detected as the first arrival wave, the estimation accuracy of a position parameter is lower than in a case where a direct wave is detected as the first arrival wave. Therefore, it can be said that the greater the difference between the delay time of the first element and the delay time of the second element, the higher the reliability.

Correlation of the CIR waveform

The reliability parameter may be derived based on a correlation of a CIR waveform at a particular antenna pair out of the plurality of antennas 221 of the communication unit 220 . In a case where a direct wave and a delayed wave are received in a combined state at the plurality of antennas 221 of the communication unit 220, a phase relationship between the direct wave and the delayed wave may be different between antennas even if the distance between the antennas is short. As a result, the CIR signal curves at the respective antennas can be different. That is, the fact that the CIR waveforms are different at a particular antenna pair means that a composite wave is being received at at least one of the antenna pairs. In a case where a composite wave is detected as the first arrival wave, i. That is, in a case where a specific item corresponding to a direct wave is not detected, the estimation accuracy of a position parameter decreases.

For example, the reliability parameter may be a correlation coefficient between a CIR obtained based on a received signal received by one antenna and a CIR obtained based on a received signal received by another antenna of the plurality of Antennas 221 of the communication unit 220 is received. In this case, it is determined that the reliability parameter is less reliable as the correlation coefficient becomes smaller, and that the reliability parameter is more reliable as the correlation coefficient becomes larger. The correlation coefficient includes, for example, a Pearson correlation coefficient.

Addition

A supplement will be described below with respect to a specific example of the reliability parameter described below.

First, each of a plurality of sample points included in a CIR is also referred to (hereinafter) as an element. That is, the CIR includes a CIR value for each delay time as an item. A form of CIR, specifically a form of a time series change in CIR value, is also referred to as a CIR waveform.

Among a variety of elements included in the CIR, a particular element is also referred to hereinafter as a particular element. The specific item is an item corresponding to the first arrival wave. The particular item is detected according to the predetermined detection criteria described above for the first arrival wave. The particular element is, for example, an element among a plurality of elements included in the CIR whose amplitude or power as a CIR value exceeds a predetermined threshold for the first time. Such a predetermined threshold value is also referred to below as a fast-path threshold value.

The time corresponding to a delay time of the specific element is used to measure a distance as a reception time of the first arrival wave. A phase of the specific element is used to estimate an angle of arrival of a signal as a phase of the first arrival wave.

The plurality of antennas 221 of the communication unit 220 may include the communication unit 220 in a Line Of Sight (LOS) state and the communication unit 220 in a Non-Line Of Sight (NLOS) state.

The LOS state means that a space between the antenna 221 of the in-vehicle device 200 and the antenna 121 of the portable device 100 can be seen. In the LOS state, the Emp capture power of a direct wave is greatest, and thus the receiving side is likely to succeed in capturing the direct wave as the first arrival wave.

The NLOS state means that the antenna 221 of the in-vehicle device 200 and the antenna 121 of the portable device 100 cannot be seen. In the NLOS state, reception power of one direct wave may be smaller than that of the others, and thus a receiving side may fail to detect the direct wave as the first arrival wave.

In a case where the communication unit 220 is in the NLOS state, reception power of a direct wave among signals arriving from the portable device 100 becomes smaller than that of noise. Even if the direct wave is successfully detected as the first arrival wave, the phase and reception time of the first arrival wave may fluctuate due to the influence of noise. In this case, the range finding accuracy and the angle-of-arrival estimation accuracy may decrease.

In a case where the communication unit 220 is in the NLOS state, reception power of a direct wave is smaller than in a case where the communication unit 220 is in the LOS state, and it can participate in detecting the direct wave as the first wave of arrivals fail. In this case, the range finding accuracy and the arrival angle estimation accuracy may decrease.

Difference between arrival time of the specific item and arrival time of an item with maximum CIR value The reliability parameter can therefore be a difference between a delay time of the specific item and a delay time of an item with the maximum CIR value in the CIR.

When the communication unit 220 is in the LOS state, a CIR value of a direct wave is largest. Therefore, an element with the maximum CIR value in the CIR is included in a set corresponding to the direct wave.

On the other hand, a CIR of a delayed wave in the NLOS state may be larger than a CIR of a direct wave. The reason for this is that in the NLOS state there is a shield in the middle of the fast path. In particular, when a human body is in the middle of the fast path, a direct wave is greatly attenuated when the direct wave passes through the human body. In this case, an element with the maximum CIR value in the CIR not included in the set corresponding to the direct wave.

Whether the communication unit 220 is in the LOS state or the NLOS state can be determined based on a difference between the delay time of the particular item and the delay time of the item with the maximum CIR value in the CIR.

This is because the difference can be small in a case where the communication unit 220 is in the LOS state. This is because the difference may be large in a case where the communication unit 220 is in the NLOS state.

The specific example of the reliability parameter according to the present embodiment has been described above. The position estimation unit 325 can improve estimation accuracy of a positional relationship between the portable device 100 and the in-vehicle device 200 using a reliability parameter calculated by the parameter calculation unit 321 .

The position estimating unit 225 may use a distance measurement value as a reliability parameter in addition to the above reliability parameter, or may use a plurality of reliability parameters in combination. Specific examples using a reliability parameter will be described in sequence below.

3. Examples

3.1. example 1

The control unit 320 regarding Example 1 may perform control for estimating a positional relationship between the portable device 100 and the in-vehicle device 200 by applying a weight parameter based on a reliability parameter calculated based on a signal received by the in-vehicle device 200 from the portable device 100 at a phase difference between adjacent antennas of the plurality of antennas 221 of the in-vehicle device perform 200.

Here, the adjacent antennas refer to the antenna 221A and the antenna 221B, the antenna 221C and the antenna 221D, the antenna 221A and the antenna 221C, the antenna 221B and the antenna 221D as shown in FIG 2 is shown.

The control unit 320 may perform weighted averaging based on a face parameter on a phase difference between antennas in directions parallel to each other among the plurality of antennas 221 and perform control to estimate a positional relationship between the portable device 100 and the in-vehicle device 200 . The antennas in the parallel direction are an antenna pair including the antenna 221A and the antenna 221B which are parallel to the X-axis described above, and an antenna pair including the antenna 221C and the antenna 221D. The antennas in the parallel direction are an antenna pair including the antenna 221A and the antenna 221C parallel to the Y-axis described above, and an antenna pair including the antenna 221B and the antenna 221D.

For example, a phase difference between antennas after weighted averaging for each pair of antennas parallel to the X axis is set as inter-antenna phase difference Pdx, and a phase difference between antennas after weighted averaging for each pair of antennas parallel to the Y axis is set as inter-antennas -phase difference Pd _Y adjusted. A weight parameter for an inter-antenna phase difference Pd _AB of the antenna 221A and the antenna 221B is set as a weight parameter W _AB , a weight parameter for an inter-antenna phase difference Pd _CD of the antenna 221C and the antenna 221D is set as a weight parameter W _CD , a weight parameter for an inter-antenna phase difference Pd _AC of the antenna 221A and the antenna 221C is set as a weight parameter W _AC , and a weight parameter for an inter-antenna phase difference Pd _BD of the antenna 221B and the antenna 221D is set as a weight parameter W _BD .

Here, the parameter calculation unit 321 can set values indicated by reliability parameters as the weight parameters W _AB , W _CD , W _AC , and W _BD , for example. For example, in a case where the reliability parameter is the above reception power, when the reception power of a signal received by the antenna 221A is "-90 dBm" and the reception power of a signal received by the antenna 221B is "-100 dBm", the weight parameter W _AB must be "-95 dBm" which is an average of "-90 dBm" and "-100 dBm". Alternatively, the weight parameter W _AB may be "-90 dBm" which is the maximum value between "-90 dBm" and "-100 dBm", or "-100 dBm" which is the minimum value. Alternatively, the weight parameter W _AB may be a median value of the reception power of the plurality of antennas 221 .

The position estimating unit 325 can estimate the inter-antenna phase difference Pdx in the X-axis direction and the inter-antenna phase difference Pd _Y in the Y-axis direction using Equation 6. $$\begin{array}{c}{\text{Pd}}_{\text{X}}=\left({\text{W}}_{\text{AWAY}}\times {\text{Pd}}_{\text{AWAY}}+{\text{W}}_{\text{CD}}\times {\text{Pd}}_{\text{CD}}\right)\text{/}\left({\text{W}}_{\text{AWAY}}+{\text{W}}_{\text{CD}}\right)\\ {\text{Pd}}_{\text{Y}}=\left({\text{W}}_{\text{AC}}\times {\text{Pd}}_{\text{AC}}+{\text{W}}_{\text{BD}}\times {\text{Pd}}_{\text{BD}}\right)\text{/}\left({\text{W}}_{\text{AC}}+{\text{W}}_{\text{BD}}\right)\end{array}$$

The position estimating unit 325 calculates the generated angle θ based on the Pd _x estimated using Equation 6 and Equation 3, and calculates the generated angle φ based on the Pd _Y estimated using Equation 6 and Equation 3. As a result, the position estimating unit 325 can estimate a positional relationship between the portable device 100 and the in-vehicle device 200 with higher accuracy.

In the example described above, an example in which the parameter calculation unit 221 sets a value indicated by a reliability parameter as a weight parameter was described, but a weight parameter is not limited to the above example. Next, another example of a method of calculating a weight parameter in the parameter calculation unit 321 will be explained with reference to FIG 6A until 7D described. First, referring to the 6A until 6D a specific example of a method of calculating a weight parameter in a case where the reliability increases as a value of the reliability parameter decreases. In the following description, a method of calculating a weight parameter based on a reliability parameter of the antenna pair of the antenna 221A and the antenna 221B will be described.

6A FIG. 12 is an explanatory diagram for describing an example of a method of calculating a weight parameter according to a first determined value. The parameter calculation unit 321 may calculate a weight parameter W based on a reliability parameter Rp and Equation 7, for example. $$\begin{array}{c}\text{W}=1\left(\text{Rp}<\text{th}\right)\\ \text{W}=0\left(\text{Rp}\ge \text{th}\right)\end{array}$$

For example, the parameter calculation unit 321 calculates a first value when the reliability parameter Rp _AB is equal to or greater than the specified value TH, and calculates a second value when the reliability parameter Rp _AB is smaller than the specified value TH.

For example, the first value can be "0" as in 6A is shown. For example, the second value can be "1" as in 6A is shown. However, the first value and the second value can be set to any values as long as the first value is less than the second value. Accordingly, the parameter calculation unit 321 can set a weight parameter according to a simpler calculation method.

The parameter calculation unit 321 may calculate the first value when the reliability parameter Rp is equal to or greater than a first specified value, and calculate the second value when the reliability parameter Rb is smaller than a second specified value that is smaller than the first specified value . The parameter calculation unit 321 may calculate a third value using a specific function when the reliability parameter Rp is equal to or larger than the second specific value and smaller than the first specific value. Here, the specific function can be, for example, a monotonically increasing or monotonically decreasing function. In this case, as the reliability parameter becomes smaller with higher reliability, the specific function is a monotonically decreasing function, and as the reliability parameter with higher reliability increases, the specific function is a monotonically increasing function. First, referring to the 6B until 6D describes a specific example of a method of calculating a weight parameter when the specific function is a monotonically decreasing function.

6B FIG. 12 is an explanatory view for describing an example of a weight parameter calculation method using a linear function as a specific function. The parameter calculation unit 321 can calculate the weight parameter W based on the reliability parameter Rp and Equation 8. $$\begin{array}{l}\begin{array}{c}\text{W}=1\left(\text{Rp}<\text{th}2\right)\\ \text{W}=-\left({\text{Rp}}_{\text{AWAY}}-\text{th}2\right)\text{/}\left(\text{<figure-callout id="1" label="th" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">th</figure-callout>}1-\text{th}2\right)+1\left(\text{<figure-callout id="2" label="th" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">th</figure-callout>}2\le \text{Rp}<\text{th}1\right)\end{array}\\ \text{W}=0\left(\text{Rp}\ge \text{th}1\right)\end{array}$$

The parameter calculation unit 321 calculates “0” as the first value when the reliability parameter Rp _AB is equal to or greater than the first specified value TH1, and calculates “1” as the second value when the reliability parameter Rp _AB is smaller than the second specified value is. The parameter calculation unit 321 may calculate the third value using a linear function as the specified function when the reliability parameter Rp _AB is equal to or larger than the second specified value TH2 and smaller than the first specified value TH1.

6C Fig. 12 is an explanatory view for describing an example of a weight parameter calculation method using a trigonometric function as a specific function. The parameter calculation unit 321 can calculate the weight parameter W based on the reliability parameter Rp and Equation 9. $$\begin{array}{l}\begin{array}{c}\text{W}=1\left(\text{Rp}<\text{th}2\right)\\ \text{W}=\text{cos}\left[\left({\text{Rp}}_{\text{AWAY}}-\text{th}2\right)\text{/}\left(\text{<figure-callout id="1" label="th" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">th</figure-callout>}1-\text{th}2\right)\times \mathrm{\pi }\text{/}2\right]\left(\text{<figure-callout id="2" label="th" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">th</figure-callout>}2\le \text{Rp}<\text{th}1\right)\end{array}\\ \text{W}=0\left(\text{Rp}\ge \text{th}1\right)\end{array}$$

The parameter calculation unit 321 calculates “0” as the first value when the reliability parameter Rp _AB is equal to or greater than the first specified value TH1, and calculates “1” as the second value when the reliability parameter Rp _AB is smaller than the second specified value is. The parameter calculation unit 321 may calculate the third value using a trigonometric function as the specified function when the reliability parameter Rp _AB is equal to or larger than the second specified value TH2 and smaller than the first specified value TH1.

6D Fig. 12 is an explanatory view for describing an example of a weight parameter calculation method using an exponential function as a specific function. The parameter calculation unit 321 can calculate the weight parameter W based on the reliability parameter Rp and Equation 10. $$\begin{array}{l}\begin{array}{c}\text{W}=1\left(\text{Rp}<\text{th}2\right)\\ \text{W}=\text{ex}\left[-5\times \left({\text{Rp}}_{\text{AWAY}}-\text{th}2\right)\text{/}\left(\text{<figure-callout id="1" label="th" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">th</figure-callout>}1-\text{th}2\right)\right]\left(\text{<figure-callout id="2" label="th" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">th</figure-callout>}2\le \text{Rp}<\text{th}1\right)\end{array}\\ \text{W}=0\left(\text{Rp}\ge \text{th}1\right)\end{array}$$

The parameter calculation unit 321 calculates “0” as the first value when the reliability parameter Rp _AB is equal to or greater than the first specified value TH1, and calculates “1” as the second value when the reliability parameter Rp _AB is smaller than the second specified value is. The parameter calculation unit 321 may calculate the third value using an exponential function as the specified function when the reliability parameter Rp _AB is equal to or larger than the second specified value TH2 and smaller than the first specified value TH1.

The specific example of the weight parameter calculation method in the case where the reliability increases as the reliability parameter Rp decreases has been described above. Subsequently, with reference to 7 describes a specific example of a method for calculating a weight parameter in a case where the reliability increases as the reliability parameter Rp increases.

7A FIG. 12 is an explanatory view for describing an example of a method of calculating a weight parameter according to the first determined value. The parameter calculation unit 321 may calculate the weight parameter W based on a reliability parameter Rp and Equation 11, for example. $$\begin{array}{l}\text{W}=0\left(\text{Rp}<\text{th}\right)\hfill \\ \text{W}=1\left(\text{Rp}\ge \text{th}\right)\hfill \end{array}$$

As in Equation 7, the parameter calculation unit 321 may calculate a first value when the reliability parameter Rp _AB is equal to or greater than the specified value TH, and may calculate a second value when the reliability parameter Rp _AB is smaller than the specified value TH.

In Equation 7, the first value can be any value as long as the first value is less than the second value, but in Equation 11, the first value is any value as long as the first value is greater than the second value. For example, the first value can be "1" as in 7A is shown. For example, the second value can be "0" as in 7A is shown.

That is, in a case where the reliability becomes higher as the reliability parameter becomes larger, the magnitude ratio between the first value and the second value described for the case where the reliability becomes higher as the reliability parameter becomes smaller is swapped. A specific example of a method for calculating a weight parameter when the specific function is a monotonically increasing function is described below with reference to FIG 7B until 7D described, and a renewed description of the 6B until 6D is omitted.

7B FIG. 12 is an explanatory diagram for describing an example of a weight parameter calculation method using a linear function as a specific function. The parameter calculation unit 321 can calculate the weight parameter W based on the reliability parameter Rp and Equation 12. $$\begin{array}{l}\begin{array}{c}\text{W}=0\left(\text{Rp}<\text{th}2\right)\\ \text{W}=-\left({\text{Rp}}_{\text{AWAY}}-\text{th}2\right)\text{/}\left(\text{<figure-callout id="1" label="th" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">th</figure-callout>}1-\text{th}2\right)+1\left(\text{<figure-callout id="2" label="th" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">th</figure-callout>}2\le \text{Rp}<\text{th}1\right)\end{array}\\ \text{W}=1\left(\text{Rp}\ge \text{th}1\right)\end{array}$$

7C Fig. 12 is an explanatory view for describing an example of a weight parameter calculation method using a trigonometric function as a specific function. The parameter calculation unit 321 can calculate the weight parameter W based on the reliability parameter Rp and Equation 13. $$\begin{array}{l}\begin{array}{c}\text{W}=0\left(\text{Rp}<\text{th}2\right)\\ \text{W}=\text{sin}\left[\left({\text{Rp}}_{\text{AWAY}}-\text{th}2\right)\text{/}\left(\text{<figure-callout id="1" label="th" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">th</figure-callout>}1-\text{th}2\right)\times \mathrm{\pi }\text{/}2\right]\left(\text{<figure-callout id="2" label="th" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">th</figure-callout>}2\le \text{Rp}<\text{th}1\right)\end{array}\\ \text{W}=1\left(\text{Rp}\ge \text{th}1\right)\end{array}$$

7D Fig. 12 is an explanatory diagram for describing an example of a weight parameter calculation method using an exponential function as a specific function. The parameter calculation unit 321 can calculate the weight parameter W based on the reliability parameter Rp and Equation 14. $$\begin{array}{l}\begin{array}{c}\text{W}=0\left(\text{Rp}<\text{th}2\right)\\ \text{W}=\text{ex}\left[5\times \left({\text{Rp}}_{\text{AWAY}}-\text{th}2\right)\text{/}\left(\text{<figure-callout id="1" label="th" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">th</figure-callout>}1-\text{th}2\right)-1\right]\left(\text{<figure-callout id="2" label="th" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">th</figure-callout>}2\le \text{Rp}<\text{th}1\right)\end{array}\\ \text{W}=1\left(\text{Rp}\ge \text{th}1\right)\end{array}$$

The parameter calculation unit 321 calculates a weight parameter using at least one of the specific examples related to the weight parameter calculation method for each antenna pair. The position estimating unit 325 calculates the inter-antenna phase difference Pd _x in the X-axis direction, and the inter-antenna phase difference Pd _y in the Y-axis direction based on the calculated weight parameter and Equation 6. The position estimating unit 325 calculates the generated angle θ and the generated angle φ of a signal as the angle of arrival of the signal based on each of the inter-antenna phase differences Pd _x and Pd _y calculated by applying the weight parameter and Equation 3. Therefore, the position estimating unit 325 can reduce the influence of the multipath environment and calculate the angle of arrival of the signal with higher accuracy.

Example of the working process

8th 12 is an explanatory diagram for describing an example of an operation process of the system 1 related to Example 1. First, the communication unit 120 included in the portable device 100 transmits a poll signal, and the communication unit 220 included in the in-vehicle device 200 receives the poll signal. signal (S201).

Thereafter, the communication unit 220 transmits a Resp signal in response to the Poll signal, and the communication unit 120 receives the Resp signal (S203).

The communication unit 120 transmits a final signal in response to the Resp signal, and the communication unit 220 receives the final signal (S205). Here, the communication unit 220 sends various kinds of information regarding the signals sent and received to and from the communication unit 120 to the communication unit 310 included in the control device 300.

Thereafter, the position estimating unit 325 calculates a distance measurement value based on the signals transmitted and received between the portable device 100 and the in-vehicle device 200 (S207).

Thereafter, the parameter calculation unit 321 calculates a reliability parameter based on the signals received by the in-vehicle device 200 (S209).

The parameter calculation unit 321 calculates a weight parameter based on the calculated reliability parameter (S211).

The position estimation unit 325 performs weighted averaging on each inter-antenna phase difference using the weight parameter calculated by the parameter calculation unit 321 (S213).

Thereafter, the position estimating unit 325 estimates an angle of arrival of the signal received from the portable device 100 using the inter-antenna phase difference subjected to the weighted averaging (S215).

The position estimating unit 325 calculates a three-dimensional position of the portable device 100 based on the estimated angle of arrival of the signal and the measured distance (S217).

The control unit 320 determines whether or not the three-dimensional position of the portable device 100 calculated by the position estimating unit 325 satisfies a predetermined criterion (S219). In a case where the predetermined criterion is met (S219: Yes), the control unit 320 causes the process to proceed to S221, and in a case where the predetermined criterion is not met (S219: No), ends the process Control unit 320 the process.

In a case where a predetermined criterion is satisfied (S219: Yes), the control unit 320 performs operation control on starting or stopping a motor that is an example of the working device 400 (S221) and the control unit 320 ends the process.

The control example regarding Example 1 has been described above. According to the control related to Example 1, the control device 300 enables the influence of multipath to be reduced and can estimate a positional relationship between the portable device 100 and the in-vehicle device 200 with higher accuracy. An example 2 is given below with reference to FIG 9 until 11 described.

3.2. example 2

The control unit 320 relating to Example 2 performs control for estimating a positional relationship between the portable device 100 and the in-vehicle device 200 by applying a weight parameter based on a reliability parameter calculated based on a signal, received by the in-vehicle device 200 from the portable device 100 in at least two preliminary positional relationships estimated based on signals transmitted and received between the in-vehicle device 200 and the portable device 100 .

For example, the position estimating unit 325 according to Example 2 estimates a tentative positional relationship between the portable device 100 and the in-vehicle device 200 based on signals transmitted and received by each antenna 221A, antenna 221B and antenna 221C and by the portable device 100. like it in 2 is shown. The position estimating unit 325 according to Example 2 estimates a preliminary positional relationship between the portable device 100 and the in-vehicle device 200 based on signals transmitted and received by each antenna 221A, antenna 221C and antenna 221D and by the portable device 100, such as it in 2 is shown. The position estimating unit 325 according to Example 2 estimates a preliminary positional relationship between the portable device 100 and the in-vehicle device 200 based on signals transmitted and received by each antenna 221B, antenna 221C and antenna 221D and by the portable device 100, such as it in 2 is shown.

The parameter calculation unit 321 calculates a reliability parameter based on a signal received by the portable device 100 for each antenna or antenna pair of the in-vehicle device 200. The parameter calculation unit 321 calculates a weight parameter based on a calculated reliability parameter using any of the example 1 described procedure.

In a case where the three preliminary positional relationships are estimated as described above, the position estimating unit 325 according to Example 2 may apply the above weight parameter to the three preliminary positional relationships to estimate a positional relationship between the portable device 100 and the in-vehicle device 200 .

Although the case where three preliminary positional relationships are estimated has been described, any number of preliminary positional relationships can be estimated as long as at least two preliminary positional relationships are estimated. As long as the number of antennas included in the in-vehicle device 200 is at least three, a method of estimating a positional relationship between the portable device 100 and the in-vehicle device 200 according to Example 2 can be applied.

Example 1, Example 2, and Example 3 are also applicable to a case where a plurality of in-vehicle devices 200 are mounted on the vehicle 20 . A case where two in-vehicle devices 200 are mounted on the vehicle 20 according to Example 2 and Example 3 will be described below.

9 FIG. 12 is a block diagram showing a configuration example of the vehicle 20 according to Example 2 and Example 3. As shown in FIG 9 As shown, the vehicle 20 is equipped with an in-vehicle device 200-1 and an in-vehicle device 200-2. The vehicle 20 may be equipped with three or more in-vehicle 200 devices. As functional configuration examples of the in-vehicle device 200, the control device 300, and the working device 400, those referring to FIG 1 are the same as those described above, their description will be omitted.

The control unit 320 according to Example 2 may perform control for estimating a positional relationship between the portable device 100 and the in-vehicle device 200 by applying a weight parameter based on a reliability parameter calculated based on a signal received from the portable device 100 by each of the plurality of in-vehicle devices 200 is calculated, on a preliminary positional relationship between the portable device 100 and the in-vehicle device 200 estimated based on a signal transmitted between each of the plurality of in-vehicle devices 200 and the portable device 100 is sent and received.

First, signals are transmitted and received between the portable device 100 and the in-vehicle device 200-1 and the in-vehicle device 200-2, and the control device 300 acquires information regarding the signals transmitted from the in-vehicle device 200-1 and the device are transmitted and received in the vehicle 200-2.

The parameter calculation unit 321 calculates a reliability parameter based on the signal received from the portable device 100 by the in-vehicle device 200 - 1 . The parameter calculation unit 321 calculates a weight parameter based on the calculated reliability parameter using any of the methods described in Example 1.

The parameter calculation unit 321 calculates a reliability parameter based on the signal received from the portable device 100 by the in-vehicle device 200 - 2 . The parameter calculation unit 321 calculates the weight parameter based on the calculated reliability parameter using any of the methods described in Example 1.

Thereafter, the position estimating unit 325 estimates an angle of arrival of the signal and a three-dimensional position of the portable device 100 based on the signal transmitted and received between the portable device 100 and the in-vehicle device 200-1. The position estimating unit 325 estimates an angle of arrival of the signal and a three-dimensional position of the portable device 100 based on the signal transmitted and received between the portable device 100 and the in-vehicle device 200 - 2 . The signal angle of incidence or the three-dimensional position of the portable device 100 estimated for each in-vehicle device 200 is a specific example of a preliminary positional relationship between the portable device 100 and the in-vehicle device 200.

The position estimation unit 325 estimates a positional relationship between the portable device 100 and the in-vehicle device 200 by applying the weight parameter calculated by the parameter calculation unit 321 to the estimated provisional positional relationship between the portable the device 100 and the in-vehicle device 200. A specific example of Example 2 will be described below with reference to FIG 10 described.

10 Fig. 12 is an explanatory view for describing a control example of the system 1 according to Example 2. As in Fig 10 1, the communication unit 220-1 included in the in-vehicle device 200-1 has an antenna 221A-1, an antenna 221B-1, an antenna 221C-1, and an antenna 221D-1. The communication unit 220-2 included in the in-vehicle device 200-2 has an antenna 221A-2, an antenna 221B-2, an antenna 221C-2, and an antenna 221D-2.

For example, in a case where the reception power is applied as a reliability parameter, it is assumed that the parameter calculation unit 321 calculates the reliability parameters of the antenna 221A-1, the antenna 221B-1 and the antenna 221C-1 to be “-90 dBm”, respectively, and calculated the reliability parameter of antenna 221D-1 to be "-105 dBm" as stated in 10 is shown. Thereafter, it is assumed that the parameter calculation unit 321 calculates the reliability parameter of the antenna 221A-2 as "-105 dBm", and the reliability parameters of the antenna 221B-2, the antenna 221C-2, and the antenna 221D-2 as "-90 dBm," respectively " calculated.

In this case, the position estimating unit 325 can estimate a positional relationship between the portable device 100 and the in-vehicle device 200 based on signals transmitted and received through three more reliable antennas, for example. For example, the position estimating unit 325 may select three antennas 221 in descending order of reliability (receiving power is high, for example), and estimate a preliminary positional relationship based on the signals transmitted and received by the selected antenna 221 .

in the in 10 In the example shown, three highly reliable antennas are, for example, the antenna 221A-1, the antenna 221B-1 and the antenna 221C-1 of the communication unit 220-1, and the antenna 221B-2, the antenna 221C-2 and the antenna 221D-2 of the communication unit 220-2.

The position estimating unit 325 estimates a tentative positional relationship based on signals transmitted and received by the antenna 221A-1, the antenna 221B-1, and the antenna 221C-1 and the antenna 121 of the portable device 100, for example. The position estimating unit 325 estimates a tentative positional relationship based on signals transmitted and received by the antenna 221B-2, the antenna 221C-2, the antenna 221D-2, and the antenna 121 of the portable device 100. FIG.

The position estimating unit 325 applies the weight parameter to each estimated preliminary positional relationship and estimates a positional relationship between the portable device 100 and the in-vehicle device 200. For example, in a case where the positional relationship between the portable device 100 and the in-vehicle device 200 is one three-dimensional position of the portable device 100 with respect to the in-vehicle device 200 is adjusted, the position estimating unit 325 applies Equation 15 and performs weighted averaging on the provisional three-dimensional position of the portable device 100 to estimate a three-dimensional position of the portable device 100 . Here, a provisional three-dimensional position of the portable device 100 estimated based on the signals transmitted and received by the portable device 100 and the in-vehicle device 200-1 is denoted by (x1,y1,z1), and a provisional three-dimensional position of the portable device 100 estimated based on the signals transmitted and received by the portable device 100 and the in-vehicle device 200-2 is denoted by (x2,y2,z2). The average received power of the device around vehicle 200-1 is denoted by P1, and the average received power of the device in the vehicle 200-2 is denoted by P2. $$\begin{array}{l}\text{X}=\left(\text{<figure-callout id="1" label="P" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">P</figure-callout>}1\times \text{x}1+\text{<figure-callout id="2" label="P" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">P</figure-callout>}2\times \text{x}2\right)\text{/}\left(\text{<figure-callout id="1" label="P" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">P</figure-callout>}1+\text{P}2\right)\hfill \\ \text{Y}=\left(\text{<figure-callout id="1" label="P" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">P</figure-callout>}1\times \text{<figure-callout id="1" label="y" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">y</figure-callout>}1+\text{<figure-callout id="2" label="P" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">P</figure-callout>}2\times \text{y}2\right)\text{/}\left(\text{<figure-callout id="1" label="P" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">P</figure-callout>}1+\text{P}2\right)\hfill \\ \text{Z}=\left(\text{<figure-callout id="1" label="P" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">P</figure-callout>}1\times \text{e.g}1+\text{<figure-callout id="2" label="P" filenames="DE102022116690A1\_0026.png,DE102022116690A1\_0028.png" state="{{state}}">P</figure-callout>}2\times \text{e.g}2\right)\text{/}\left(\text{<figure-callout id="1" label="P" filenames="DE102022116690A1\_0016.png,DE102022116690A1\_0020.png" state="{{state}}">P</figure-callout>}1+\text{P}2\right)\hfill \end{array}$$

Equation 15 is an example of calculating a weighted average when an average of the reliability parameters (average received powers P1 and P2) is applied as the weight parameter. As the weight parameter, a weight parameter based on a reliability parameter can be calculated using each equation described in Example 1.

Example of the working process

11 12 is an explanatory diagram for describing an example of an operation process of the system 1 according to Example 2. First, the communication unit 120 included in the portable device 100 transmits a poll signal, and the communication unit 220-1 included in the in-vehicle device 200-1 and the communication unit 220-2 included in the in-vehicle device 200-2 receive the poll signal (S301).

Thereafter, the communication unit 220-1 and the communication unit 220-2 transmit a Resp signal in response to the Poll signal, and the communication unit 120 receives the Resp signal (S303).

The communication unit 120 transmits a final signal in response to the Resp signal, and the communication unit 220-1 and the communication unit 220-2 receive the final signal (S305). Here, the communication unit 220-1 and the communication unit 220-2 send various kinds of information regarding the transmitted and received signals to the communication unit 310 included in the control device 300.

Thereafter, the position estimating unit 325 calculates a first distance measurement value based on the signals transmitted and received between the portable device 100 and the in-vehicle device 200-1, and calculates a second distance measurement value based on the signals between the portable device 100 and the in-vehicle device 200- 2 transmitted and received signals (S307).

Thereafter, the parameter calculation unit 321 calculates a first reliability parameter based on the signal received by the in-vehicle device 200-1 and calculates a second reliability parameter based on the signal received by the in-vehicle device 200-2 (S309).

The parameter calculation unit 321 calculates a weight parameter based on each calculated reliability parameter (S311). For example, the parameter calculation unit 321 calculates a first weight parameter based on the first reliability parameter and calculates a second weight parameter based on the second reliability parameter.

The position estimating unit 325 estimates an angle of arrival of a first signal based on the signals transmitted and received between the portable device 100 and the in-vehicle device 200-1, and estimates an angle of arrival of a second signal based on the signals between the portable device 100 and the device in-car vehicle 200-2 transmitted and received signals (S313).

Thereafter, the position estimating unit 325 estimates a first provisional three-dimensional position of the portable device 100 based on the angle of arrival of the first signal and estimates a second provisional three-dimensional position of the portable device 100 based on the angle of arrival of the second signal (S315).

The position estimating unit 325 performs weighted averaging on the first provisional three-dimensional position and the second provisional three-dimensional position of the portable device 100 based on the first weight parameter and the second weight parameter, and estimates a three-dimensional position of the portable device 100 (S317).

The control unit 320 determines whether or not the weighted average estimated three-dimensional position of the portable device 100 satisfies a predetermined criterion (S319). In a case where the predetermined criterion is met (S319: Yes), the control unit 320 causes the process to proceed to S321, and in a case where the predetermined criterion is not met (S319: No), ends the process Control unit 320 the process.

In a case where the predetermined criterion is satisfied (S319: Yes), the control unit 320 performs operation control related to starting or stopping the engine, which is an example of the working device 400 (S321), and the control unit 320 ends the process.

The control example according to Example 2 has been described above. According to the control of Example 2, the control device 300 enables the influence of multipath to be reduced and can estimate a positional relationship between the portable device 100 and the in-vehicle device 200 with higher accuracy.

Example 1 and Example 2 described an example in which the position estimating unit 325 calculates two weight parameters based on signals transmitted and received by the in-vehicle device 200-1 and the in-vehicle device 200-2, respectively, and the applies weight parameters to a calculation process or a calculation result of a positional relationship between the portable device 100 and the in-vehicle device 200 . As described above, by using a weight parameter based on a reliability parameter, the influence of a calculation error due to the multipath environment can be reduced. The control unit 320 may select the in-vehicle device 200 that is less affected by the multipath environment based on the reliability parameters based on signals transmitted and received by the in-vehicle device 200-1 and the in-vehicle device 200-2 become. Example 3 will be described below with reference to FIG 12 until 14 described.

3.3. Example 3

12 12 shows an explanatory view for describing a control example of the system 1 according to Example 3. The control unit 320 according to Example 3 compares reliability parameters calculated based on signals received by each of the plurality of in-vehicle devices 200 from the portable device 100 , and performs control for estimating a positional relationship based on signals transmitted and received between the in-vehicle device 200, which has transmitted a signal more suitable as a processing target for estimating the positional relationship, and the portable device 100. In the following description, a reliability parameter is described as receiving power of a signal received by the antenna 221, but may be another reliability parameter described above.

For example, the antenna 221A-1, the antenna 221B-1, the antenna 221C-1 and the antenna 221D-1 of the communication unit 220-1 included in the in-vehicle device 200-1 receive a final signal from the antenna 121 of the device shown in FIG portable device 100 included communication unit 120. Here, it is assumed that the receiving power of the antenna 221A-1 is "-90 dBm", the receiving power of the antenna 221B-1 is "-95 dBm", the receiving power of the antenna 221C-1 is "-95 dBm” and the receiving power of the antenna 221D-1 is “-100 dBm”.

The antenna 221A-2, the antenna 221B-2, the antenna 221C-2 and the antenna 221D-2 of the communication unit 220-2 included in the in-vehicle device 200-2 receive a final signal from the antenna 121 of the in-vehicle Device 100 includes communication unit 120. Here, it is assumed that the receiving power of antenna 221A-2 is "-99 dBm", the receiving power of antenna 221B-2 is "-99 dBm", the receiving power of antenna 221C-2 is "-101 dBm ", and the receiving power of the antenna 221D-2 is "-101 dBm".

In this case, the parameter calculation unit 321 calculates a basic statistic based on the reliability parameter (e.g. the received power) estimated for each antenna. For example, the base statistic can be a mean, maximum, minimum, or median value.

For example, when the basic statistics are averaged, the parameter calculation unit 321 can calculate “-95 dBm” as an average of the received powers of the antenna 221A-1, the antenna 221B-1, the antenna 221C-1, and the antenna 221D-1. The parameter calculation unit 321 can calculate “-100 dBm” as an average of the reception powers of the antenna 221A-2, the antenna 221B-2, the antenna 221C-2 and the antenna 221D-2.

The position estimating unit 325 compares "-95 dBm" which is an average of the reception powers of the antenna 221A-1, the antenna 221B-1, the antenna 221C-1 and the antenna 221D-1 with "-100 dBm" , which is an average of the reception powers of the antenna 221A-2, the antenna 221B-2, the antenna 221C-2 and the antenna 221D-2.

The position estimating unit 325 selects the communication unit 220 that is more suitable (ie, highly reliable) as a processing target for estimating a positional relationship. For example, the position estimating unit 325 may estimate a positional relationship between the portable device 100 and the in-vehicle device 200-1 based on a signal transmitted between the communication unit 220-1 including the antenna 221-1 having a larger average value of reception power, and of the communication unit 120 included in the portable device 100 is transmitted and received.

The position estimating unit may select three antennas from four or more antennas in each of the plurality of in-vehicle devices 200 based on a reliability parameter. The position estimating unit 325 may compare reliability parameters calculated based on signals received by the three selected antennas, respectively. The position estimating unit 325 may estimate a positional relationship between the portable device 100 and the in-vehicle device 200 based on a signal transmitted between the in-vehicle device 200 that has received a signal transmitted based on a result of the comparison as a processing target for estimation a positional relationship is more appropriate and the portable device 100 is transmitted and received.

13 12 is an explanatory diagram for describing another control example of the system 1 according to Example 3. For example, the antenna 221A-1, the antenna 221B-1, the antenna 221C-1 and the antenna 221D-1 of the in-vehicle device 200-1 receive The communication unit 220-1 included in the communication unit 220-1 receives a final signal from the antenna 121 of the communication unit 120 included in the portable device 100. Here, it is assumed that the receiving power of the antenna 221A-1 is "-89 dBm", the receiving power of the antenna 221B-1 is " -89 dBm", the receiving power of antenna 221C-1 is "-89 dBm", and the receiving power of antenna 221D-1 is "-105 dBm". In this case, the position estimating unit 325 may select the antenna 221A-1, the antenna 221B-1, and the antenna 221C-1 in descending order of reception power.

The antenna 221A-2, the antenna 221B-2, the antenna 221C-2 and the antenna 221D-2 of the communication unit 220-2 included in the in-vehicle device 200-2 receive the final signal from the antenna 121 of the in the portable Device 100 includes communication unit 120. Here, it is assumed that the receiving power of the antenna 221A-2 is "-105 dBm", the receiving power of the antenna 221B-2 is "-90 dBm", the receiving power of the antenna 221C-2 is "-90 dBm ", and the receiving power of the antenna 221D-2 is "-90 dBm". In this case, the position estimating unit 325 may select the antenna 221B-2, the antenna 221C-2, and the antenna 221D-2 in descending order of reception power.

In a case where each of the plurality of in-vehicle devices 200 has N (where 4≦N) antennas, the position estimating unit 325 may have M (where 3≦M≦N) antennas out of the N antennas in each of the plurality of devices in the vehicle 200 based on a reliability parameter.

Thereafter, the position estimating unit 325 compares reliability parameters calculated based on signals received by the respective three antennas selected for the in-vehicle device 200-1 and the in-vehicle device 200-2, respectively.

In a case where a method of comparing average reliability parameter values of the respective antennas 221 is applied, the position estimating unit 325 obtains a comparison result that the average reception power of the antenna 221A-1, the antenna 221B-1 and the antenna 221C-1 of the In-vehicle device 200-1 is higher than that of antenna 221B-2, antenna 221C-2 and antenna 221D-2 of in-vehicle device 200-2, and a signal more suitable as a processing target for estimating a positional relationship is transmitted and was received.

The position estimating unit 325 performs a process of estimating a positional relationship between the portable device 100 and the in-vehicle device 200-1 based on signals transmitted between the in-vehicle device 200-1 that transmitted and received the signal designated as processing target is more suitable for estimating a positional relationship, and the portable device 100 can be transmitted and received. The positional relationship between the portable device 100 and the in-vehicle device 200 - 1 may be an angle of incidence of a signal, or may be a two-dimensional position or a three-dimensional position of the portable device 100 as in Example 1 and Example 2.

The position estimating unit 325 may select, of each of the plurality of in-vehicle devices 200 , an antenna whose reliability parameter based on a received signal satisfies a certain criterion from four or more antennas of each of the plurality of in-vehicle devices 200 . For example, the position estimating unit 325 may select, of each of the plurality of in-vehicle devices 200 , an antenna whose received signal-based reliability parameter is a predetermined value from four or more antennas of each of the plurality of in-vehicle devices 200 . More specifically, for example, in a case where a reliability parameter is reception power and a predetermined value is “-90 dBm”, the position estimating unit 325 may select an antenna in which the reception power of a received signal is greater than or equal to “-90 dBm”. select the four or more antennas. The position estimation unit 325 may compare reliability parameters of the selected antennas at each of the plurality of in-vehicle devices 200 .

Example of the working process

14 12 is an explanatory view for describing an example of an operation process of the system 1 according to Example 3. In the following description, an operation process in a case where the reliability of a transmitted and received signal becomes higher as a value of a reliability parameter becomes smaller will be described. First, the communication unit 120 included in the portable device 100 transmits a poll signal, and the communication unit 220-1 included in the in-vehicle device 200-1 and the communication unit 220-2 included in the in-vehicle device 200-2 receive the poll signal (S401).

Thereafter, the communication unit 220-1 and the communication unit 220-2 send a Resp signal in response to the Poll signal, and the communication unit 120 receives the Resp signal (S403).

The communication unit 120 transmits a final signal in response to the Resp signal, and the communication unit 220-1 and the communication unit 220-2 receive the final signal (S405). Here, the communication unit 220-1 and the communication unit 220-2 send various kinds of information regarding the transmitted and received signals to the communication unit 310 included in the control device 300.

Thereafter, the position estimating unit 325 calculates a first distance measurement based on the signals transmitted and received between the portable device 100 and the in-vehicle device 200-1, and calculates a second distance measurement based on the signals transmitted between the portable device 100 and the in-vehicle device 200-2 are transmitted and received (S407).

Thereafter, the parameter calculation unit 321 calculates a first reliability parameter based on the signal received by the in-vehicle device 200-1 and calculates a second reliability parameter based on the signal received by the in-vehicle device 200-2 (S409).

The control unit 320 determines whether or not the reliability parameter based on the signal received by the in-vehicle device 200-1 is greater than the reliability parameter based on the signal received by the in-vehicle device 200-2 (S413). In a case where the reliability parameter based on the signal received by the in-vehicle device 200-1 is larger (S413: Yes), the control unit 320 causes the process to proceed to S415, and in a case in where the reliability parameter based on the signal received by the in-vehicle device 200-2 is larger (S413: No), the control unit 320 causes the process to proceed to S419.

In a case where the reliability parameter based on the signal received by the in-vehicle device 200-1 is larger (S413: Yes), the position estimating unit 325 estimates an angle of arrival of a signal based on the signal received by the in-vehicle device 200-1 of the communication unit 220-2 included in the in-vehicle device 200-2 is transmitted and received (S415).

The position estimating unit 325 estimates a three-dimensional position of the portable device 100 based on the estimated angle of arrival of the signal and the second distance measurement value (S417).

In a case where the reliability parameter based on the signal received by the in-vehicle device 200-2 is larger (S413: No), the position estimating unit 325 estimates an angle of arrival of a signal based on the signal received by the in-vehicle device 200-2 of the communication unit 220-1 included in the in-vehicle device 200-1 is transmitted and received (S419).

The position estimating unit 325 estimates a three-dimensional position of the portable device 100 based on the estimated angle of arrival of the signal and the first measured distance (S421).

The control unit 320 determines whether or not the estimated three-dimensional position of the portable device 100 satisfies a predetermined criterion (S423). In a case where the predetermined criterion is met (S423: Yes), the control unit 320 causes the process to proceed to S425, and in a case where the predetermined criterion is not met (S423: No), ends the process Control unit 320 the process.

In a case where the predetermined criterion is satisfied (S423: Yes), the control unit 320 performs operation control related to starting or stopping the engine, which is an example of the working device 400 (S425) , and the control unit 320 ends the process.

A working process of the system 1 according to example 3 was described above. A working process in a case where there are a plurality of devices in the vehicle 200 is not limited to the above example. For example, after sending and receiving a poll signal, a resp signal, and a final signal between the communication unit 120 included in the portable device 100 and the communication unit 220-1 included in the in-vehicle device 200-1, a poll signal , a resp signal, and a final signal are transmitted and received between the communication unit 120 and the communication unit 220-2 included in the in-vehicle device 200-2. The position estimating unit 325 may estimate a first three-dimensional position of the portable device 100 based on the signals transmitted and received between the portable device 100 and the in-vehicle device 200-1 and a second three-dimensional position of the portable device 100 based thereon of the signals transmitted and received between the portable device 100 and the in-vehicle device 200-2, and then the control unit 320 may compare reliability parameters. For example, in a case where it is determined that the in-vehicle device 200-1 has transmitted and received a signal having higher reliability than a signal of the in-vehicle device 200-2, the control unit 320 may set the first three-dimensional position as adjust a three-dimensional position of the portable device 100 .

According to the control of Example 3 described above, the control device 300 can estimate a positional relationship between the portable device 100 and the in-vehicle device 200 with higher accuracy by selecting the in-vehicle device 200 having less affection from multipath.

Although the details of Example 1, Example 2 and Example 3 have been described, the control device 30 according to the present embodiment can perform control by combining the above Example 1 with Example 2 or Example 3.

For example, in a case where Example 1 is combined with Example 2, the position estimating unit 325 performs weighted averaging using a reliability parameter-based weight parameter on an inter-antenna phase difference of an antenna pair of the in-vehicle device 200-1. The position estimating unit 325 estimates an angle of arrival of a signal and a provisional three-dimensional position of the portable device 100 based on the inter-antenna phase difference subjected to the weighted averaging. The position estimation unit 325 estimates an angle of arrival of a signal and a provisional three-dimensional position of the portable device 100 through the same process in the in-vehicle device 200-2. The position estimating unit 325 may then perform a reliability parameter-based weighted averaging on the estimated two preliminary three-dimensional positions of the portable device 100 to estimate a three-dimensional position of the portable device 100 .

In a case where Example 1 is combined with Example 3, for example, the position estimating unit 325 compares respective reliability parameters of the in-vehicle device 200-1 and the in-vehicle device 200-2, and selects the in-vehicle device 200 to estimate a positional relationship to the portable device 100 according to a result of the comparison. Next, the position estimating unit 325 performs weighted averaging using a weight parameter based on a reliability parameter on the inter-antenna phase difference of the antenna pair of the selected in-vehicle device 200 . The position estimating unit 325 may estimate an angle of arrival of a signal and a three-dimensional position of the portable device 100 based on the inter-antenna phase difference subjected to the weighted averaging.

According to the control in the above combination of Example 1 and either of Examples 2 or 3, the control device 30 can estimate a positional relationship between the portable device 100 and the in-vehicle device 200 with higher accuracy.

4. Appendix

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that those skilled in the art can invent various changes or modifications within the scope of the technical idea disclosed in the claims, and these naturally also belong to the technical scope of the present invention.

For example, a variety of processes may be implemented by any device described in this application using software, hardware, or a combination of software and hardware. A program constituting the software is stored in advance, for example, on a recording medium (non-volatile medium) provided inside or outside each device. This program is read into a RAM by a computer at the time of execution and executed by a processor such as a CPU. The recording medium is, for example, a magnetic disk, an optical disk, a magneto-optical disk, or a flash memory. For example, the above computer program can be distributed over a network instead of using a recording medium.

The steps involved in completing the operation of the system 1 according to the present embodiment need not necessarily be performed in the order described as an illustrative representation in terms of time. For example, each step in completing the operation of system 1 may be processed in an order different than that described in the illustrative illustration, or may be performed in parallel.

A positional relationship between devices that have transmitted and received signals is estimated with higher accuracy. A control device includes a control unit that compares reliability parameters, which are indexes indicating a degree of whether or not a signal is appropriate as a processing target for estimating a positional relationship between each communication device of a plurality of communication devices and another communication device, based on of the signals received by the communication device from the other communication device, and performs control to estimate the positional relationship based on a signal transmitted between one communication device of the plurality of communication devices that has received a signal designated as a processing target for estimation of the positional relationship is more appropriate, and the other communication device is transmitted and received.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• JP 2021143138 [0001]
• WO 2015176776 A [0003, 0004]

Claims (13)

Control device with: a control unit for performing control for estimating a positional relationship between a plurality of communication devices each having three or more antennas and another communication device based on signals transmitted and received between the plurality of communication devices and the other communication device, wherein the control unit for comparing reliability parameters, which are indexes indicating a degree of whether or not a signal is suitable as a processing target for estimating a positional relationship between each one of the plurality of communication devices and the other communication device, which calculates based on the signals received by the communication device from the other communication device, and performing control for estimating the positional relationship based on a signal established between a communication device of the plurality of communication devices that has received a signal designated as a processing target for estimating the Positional relationship is more appropriate, and the other communication device is transmitted and received. control device claim 1 wherein the control unit compares basic statistics based on reliability parameters estimated for the respective three or more antennas or for respective pairs of antennas of each communication device of the plurality of communication devices, and performs control for estimating the positional relationship based on a signal, that is transmitted and received between the communication device that has received a signal more suitable as a processing target for estimating the positional relationship determined based on a result of the comparison and the other communication device. control device claim 2 , where the basic statistical information includes a mean value and/or a maximum value and/or a minimum value and/or a median value. control device claim 1 , wherein the three or more antennas are four or more antennas, and the control unit selects three antennas from the four or more antennas of each of the plurality of communication devices based on the reliability parameters, the reliability parameters calculated based on the signal that received by each of the three selected antennas, and performs control to estimate the positional relationship based on a signal received between the communication device that has received a signal that is more appropriate as a processing target for estimating the positional relationship based on a result of the comparison is, and the other communication device is transmitted and received. control device claim 1 , wherein the three or more antennas are four or more antennas, and the control unit selects an antenna for which the reliability parameter satisfies a certain criterion from the four or more antennas of each of the plurality of communication devices, compares reliability parameters for the plurality of respective communication devices, which are calculated based on a signal received by each of the selected antennas and performs control for estimating the positional relationship based on a signal transmitted between the communication device which has received a signal based on a result of the comparison is more suitable as a processing target for estimating the positional relationship, and the other communication device is transmitted and received. control device claim 1 wherein the control unit estimates an angle of incidence of the signal received by the communication device from the other communication device as the positional relationship between the communication device and the other communication device. control device claim 6 wherein the control unit estimates a two-dimensional position or a three-dimensional position of the other communication device as the positional relationship between the communication device and the other communication device based on the angle of arrival of the signal. control device claim 1 wherein the reliability parameters include an index indicating a magnitude of noise of a signal received by the communication device and/or the other communication device and/or an index indicating a validity that the signal is based on a direct wave. control device claim 1 wherein the communication device is attached to a moving object. control device claim 9 wherein the other communication device is carried by a user using the moving object. control device claim 1 , wherein the signals include a wireless signal conforming to ultra-wideband wireless communication. System with: a plurality of communication devices each having three or more antennas, another communication device having one or more antennas, and a control device that performs control to estimate a positional relationship between the plurality of communication devices and the other communication device based on signals transmitted and received between the plurality of communication devices and the other communication device, wherein the control device compares reliability parameters, which are indexes indicating a degree of whether or not a signal is suitable as a processing target for estimating a positional relationship between each one of the plurality of communication devices and the other communication device calculated based on the signals, received by the communication device from the other communication device, and performs control for estimating the positional relationship based on a signal transmitted between a communication device of the plurality of communication devices that has received a signal more suitable as a processing target for estimating the positional relationship, and the other communication device is transmitted and received. Control method executed by a computer, comprising: transmitting and receiving signals between a plurality of communication devices each having three or more antennas and another communication device, and performing control to estimate a positional relationship between the plurality of communication devices and the other communication device based on the transmitted and received signals, wherein performing the control for estimating a positional relationship between the plurality of communication devices and the other communication device comprises: Comparing reliability parameters, which are indexes indicating a degree of whether or not a signal is suitable as a processing target for estimating a positional relationship between each one of the plurality of communication devices and the other communication device, which are calculated based on the signals that received by the communication device from the other communication device, and performing control for estimating the positional relationship based on a signal transmitted between a communication device of the plurality of communication devices that has received a signal more suitable as a processing target for estimating the positional relationship, and of the other communication device is transmitted and received.

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